class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots())

N,K = map(int,input().split())
P = list(map(int,input().split()))
C = list(map(int,input().split()))
uf = UnionFind(N)
ans = -10**9
for i in range(N):
    uf.union(i,P[i]-1)
for group in uf.all_group_members().values():
    size = len(group)
    SUM = 0
    for i in group:
        SUM += C[i]
    if SUM < 0:
        SUM = 0
    for i in group:
        cur = i
        current_sum = 0
        remain = K
        for _ in range(size):
            cur = P[cur]-1
            current_sum += C[cur]
            remain -= 1
            if remain < 0:
                break
            ans = max(ans,current_sum+SUM*(remain//size))
print(ans) class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) UnionFind def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

     __init__ self.n = n self.n self n n self.parents = [-1] * n self.parents self parents [-1] * n [-1] -1 n self self n n def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

     find if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

     self.parents[x] < 0 self.parents[x] self.parents self parents x 0 return x x self.parents[x] = self.find(self.parents[x]) self.parents[x] self.parents self parents x self.find(self.parents[x]) self.find self find self.parents[x] self.parents self parents x return self.parents[x] self.parents[x] self.parents self parents x self self x x def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

     union x = self.find(x) x self.find(x) self.find self find x y = self.find(y) y self.find(y) self.find self find y if x == y:
            return

         x == y x y return if self.parents[x] > self.parents[y]:
            x, y = y, x

         self.parents[x] > self.parents[y] self.parents[x] self.parents self parents x self.parents[y] self.parents self parents y x, y = y, x x y y x self.parents[x] += self.parents[y] self.parents[x] self.parents self parents x self.parents[y] self.parents self parents y self.parents[y] = x self.parents[y] self.parents self parents y x self self x x y y def size(self, x):
        return -self.parents[self.find(x)]

     size return -self.parents[self.find(x)] -self.parents[self.find(x)] self.parents[self.find(x)] self.parents self parents self.find(x) self.find self find x self self x x def same(self, x, y):
        return self.find(x) == self.find(y)

     same return self.find(x) == self.find(y) self.find(x) == self.find(y) self.find(x) self.find self find x self.find(y) self.find self find y self self x x y y def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

     members root = self.find(x) root self.find(x) self.find self find x i for i in range(self.n) if self.find(i) == root for i in range(self.n) if self.find(i) == root i range(self.n) range self.n self n self.find(i) == root self.find(i) self.find self find i root if self.find(i) == root i return [i for i in range(self.n) if self.find(i) == root] [i for i in range(self.n) if self.find(i) == root] self self x x def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

     roots i for i, x in enumerate(self.parents) if x < 0 for i, x in enumerate(self.parents) if x < 0 i x enumerate(self.parents) enumerate self.parents self parents x < 0 x 0 if x < 0 i return [i for i, x in enumerate(self.parents) if x < 0] [i for i, x in enumerate(self.parents) if x < 0] self self def group_count(self):
        return len(self.roots())

     group_count return len(self.roots()) len(self.roots()) len self.roots() self.roots self roots self self def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

     all_group_members r: self.members(r) for r in self.roots() for r in self.roots() r self.roots() self.roots self roots for r in self.roots() r self.members(r) self.members self members r return {r: self.members(r) for r in self.roots()} {r: self.members(r) for r in self.roots()} self self def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) __str__ return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) '\n'.join '\n' join '{}: {}'.format(r, self.members(r)) '{}: {}'.format '{}: {}' format r self.members(r) self.members self members r self self N,K = map(int,input().split()) N map(int,input().split()) map int input().split() ().split () input split K P = list(map(int,input().split())) P list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split C = list(map(int,input().split())) C list(map(int,input().split())) list map(int,input().split()) map int input().split() ().split () input split uf = UnionFind(N) uf UnionFind(N) UnionFind N ans = -10**9 ans -10**9 -10 9 for i in range(N):
    uf.union(i,P[i]-1) i range(N) range N uf.union(i,P[i]-1) uf.union uf union i P[i]-1 P[i] P i 1 for group in uf.all_group_members().values():
    size = len(group)
    SUM = 0
    for i in group:
        SUM += C[i]
    if SUM < 0:
        SUM = 0
    for i in group:
        cur = i
        current_sum = 0
        remain = K
        for _ in range(size):
            cur = P[cur]-1
            current_sum += C[cur]
            remain -= 1
            if remain < 0:
                break
            ans = max(ans,current_sum+SUM*(remain//size)) group uf.all_group_members().values() uf.all_group_members().values uf.all_group_members() uf.all_group_members uf all_group_members values size = len(group) size len(group) len group SUM = 0 SUM 0 for i in group:
        SUM += C[i]
     i group SUM += C[i] SUM C[i] C i if SUM < 0:
        SUM = 0
     SUM < 0 SUM 0 SUM = 0 SUM 0 for i in group:
        cur = i
        current_sum = 0
        remain = K
        for _ in range(size):
            cur = P[cur]-1
            current_sum += C[cur]
            remain -= 1
            if remain < 0:
                break
            ans = max(ans,current_sum+SUM*(remain//size)) i group cur = i cur i current_sum = 0 current_sum 0 remain = K remain K for _ in range(size):
            cur = P[cur]-1
            current_sum += C[cur]
            remain -= 1
            if remain < 0:
                break
            ans = max(ans,current_sum+SUM*(remain//size)) _ range(size) range size cur = P[cur]-1 cur P[cur]-1 P[cur] P cur 1 current_sum += C[cur] current_sum C[cur] C cur remain -= 1 remain 1 if remain < 0:
                break
             remain < 0 remain 0 break ans = max(ans,current_sum+SUM*(remain//size)) ans max(ans,current_sum+SUM*(remain//size)) max ans current_sum+SUM*(remain//size) current_sum SUM*(remain//size) SUM remain//size remain size print(ans) print ans N,K = map(int,input().split()) map(int,input().split()) N C = list(map(int,input().split())) list(map(int,input().split())) C SUM += C[i] C[i] SUM cur = i i cur SUM = 0 0 SUM ans = -10**9 -10**9 ans cur = P[cur]-1 P[cur]-1 cur K = map(int,input().split()) map(int,input().split()) K uf = UnionFind(N) UnionFind(N) uf remain = K K remain P = list(map(int,input().split())) list(map(int,input().split())) P current_sum += C[cur] C[cur] current_sum remain -= 1 1 remain ans = max(ans,current_sum+SUM*(remain//size)) max(ans,current_sum+SUM*(remain//size)) ans class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots()) UnionFind size = len(group) len(group) size current_sum = 0 0 current_sum SUM = 0 0 SUM
class UnionFind():
    def __init__(self, n):
        self.n = n
        self.parents = [-1] * n

    def find(self, x):
        if self.parents[x] < 0:
            return x
        else:
            self.parents[x] = self.find(self.parents[x])
            return self.parents[x]

    def union(self, x, y):
        x = self.find(x)
        y = self.find(y)

        if x == y:
            return

        if self.parents[x] > self.parents[y]:
            x, y = y, x

        self.parents[x] += self.parents[y]
        self.parents[y] = x

    def size(self, x):
        return -self.parents[self.find(x)]

    def same(self, x, y):
        return self.find(x) == self.find(y)

    def members(self, x):
        root = self.find(x)
        return [i for i in range(self.n) if self.find(i) == root]

    def roots(self):
        return [i for i, x in enumerate(self.parents) if x < 0]

    def group_count(self):
        return len(self.roots())

    def all_group_members(self):
        return {r: self.members(r) for r in self.roots()}

    def __str__(self):
        return '\n'.join('{}: {}'.format(r, self.members(r)) for r in self.roots())

N,K = map(int,input().split())
P = list(map(int,input().split()))
C = list(map(int,input().split()))
uf = UnionFind(N)
ans = -10**9
for i in range(N):
    uf.union(i,P[i]-1)
for group in uf.all_group_members().values():
    size = len(group)
    SUM = 0
    for i in group:
        SUM += C[i]
    if SUM < 0:
        SUM = 0
    for i in group:
        cur = i
        current_sum = 0
        remain = K
        for _ in range(size):
            cur = P[cur]-1
            current_sum += C[cur]
            remain -= 1
            if remain < 0:
                break
            ans = max(ans,current_sum+SUM*(remain//size))
print(ans)